It’ll get better when you start understanding it
Answer:
f(x) = (x + 4)² - 3
Step-by-step explanation:
The equation of a quadratic function in vertex form is
y = a(x - h)² + k
where (h, k) are the coordinates of the vertex and a is a multiplier
Given
f(x) = x² + 8x + 13
To obtain f(x) in vertex form use the method of completing the square
add/ subtract (half the coefficient of the x- term)² to x² + 8x
f(x) = x² + 2(4)x + 16 - 16 + 13
f(x) = (x + 4)² - 3 ← in vertex form
Answer:
x = −4
Step-by-step explanation:
Add x to both sides of the equation. x + 4 + x = − 4 Add x and x . 2 x + 4 = −4
Subtract 4 from both sides of the equation. 2 x = −4 − 4 Subtract 4 from - 4. 2x = −8
Divide each term in 2x = −8 by 2. 2x/2 = −8/2
Cancel the common factor. 2x/ 2 = −8/2 Divide x by 1. x = −8/2
Divide −8 by 2. x = −4